Discrete Mathematics (3140708) MCQs

MCQs of Algebraic Structures

Showing 11 to 20 out of 65 Questions
1 2 3 4 5 6
11.
Let * be a binary operation on ℝ defined by a*b=a+b+2ab then 7*(1/2)= ?
(a) 13.5
(b) 14.5
(c) 15.5
(d) 16.5
Answer:

Option (b)

12.
Let * be a binary operation on ℝ defined by a*b=a+b+2ab then find the identity element w.r.t. *.
(a) 0
(b) 1
(c) 2
(d) 3
Answer:

Option (a)

13.
The elements of the group of cube root of unity are _____.
(a) 1, 1±3i2
(b) 0, 1±3i2
(c) 1, -1±3i2
(d) 0, -1±3i2
Answer:

Option (c)

14.
Let G={1,-1,i,-i} is group under multiplication then how many elements are self invertible in G?
(a) 1
(b) 2
(c) 3
(d) 4
Answer:

Option (b)

15.
Let G={1,-1,i,-i} is group under multiplication then the inverse of i is _____.
(a) 1
(b) -1
(c) i
(d) -i
Answer:

Option (d)

16.
Which of the following is group under multiplication?
(a) ℚ
(b) ℚ-{0}
(c) ℚ-{1}
(d) ℚ-{0,1}
Answer:

Option (b)

17.
Let G=ℚ+ and a*b=ab2, ∀a, b∈ℚ+. The identity element of G is _____.
(a) 0
(b) 1
(c) 2
(d) 3
Answer:

Option (c)

18.
Let G=ℚ+ and a*b=ab2, ∀a, b∈ℚ+. The inverse of a is _____.
(a) 1/a
(b) 2/a
(c) 3/a
(d) 4/a
Answer:

Option (d)

19.
Let G=(ℤ6, +6) is an Abelian group then how many self invertible elements in G?
(a) 1
(b) 2
(c) 3
(d) 4
Answer:

Option (b)

20.
Let G=(ℤ6, +6) is an Abelian group then the inverse element of 4 is _____.
(a) 0
(b) 1
(c) 2
(d) 3
Answer:

Option (c)

Showing 11 to 20 out of 65 Questions
1 2 3 4 5 6